The present invention relates to an anti-inflammatory agent comprising as an active component a human urinary thiol protease inhibitor and a process for preparation thereof.
Human urinary proteins are composed mainly of albumin [see "Sogo Rinsho", Vol. 27, P. 1223 (1978)], and it is known that human urinary proteins contain enzymes such as urokinase or kallikrein and inhibitors such as a human urinary trypsin inhibitor as a serine enzyme inhibitor [see J. Biochem., Vol. 88, P. 1317 (1980)].
Recently, enzyme inhibitors present in human urine has been examined and a substance inhibiting ficin, a kind of a thiol protease, has newly been found [see Proc. Soc. Exp. Biol. and Med., Vol 167, P. 530 (1981)]. However, this substance has not been elucidated in detail and the biological significance of this substance has been unknown.
We, the inventors, made researches on extraction and purification of a thiol protease inhibitor from human urine and biochemical properties of this inhibitor and as the result, we found that this inhibitor is different from a urinary trypsin inhibitor and specifically inhibits the action of a thiol protease. We furthered our researches on the medicinal utility of this inhibitor and found that this inhibitor has an anti-inflammatory action. We have now completed the present invention based on these findings.